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<TITLE>[Chapter 24] 24.17 java.io.FileDescriptor (JDK 1.0)</TITLE>
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<h2 CLASS=sect1><A CLASS="TITLE" NAME="JNUT2-CH-24-SECT-17">24.17 java.io.FileDescriptor (JDK 1.0)</A></h2>

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<h3 CLASS=sect2><A CLASS="TITLE" NAME="JNUT2-CH-24-SECT-17.1"></A></h3>
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<P CLASS=para>
This class is a platform-independent representation of a
low-level handle to an open file or an open socket.
The static <tt CLASS=literal>in</tt>, <tt CLASS=literal>out</tt>, and <tt CLASS=literal>err</tt>
variables are <tt CLASS=literal>FileDescriptor</tt> objects that represent
the system standard input, output, and error streams,
respectively. There is no public constructor method to
create a <tt CLASS=literal>FileDescriptor</tt> object. You can obtain one
with the <tt CLASS=literal>getFD()</tt> method of <tt CLASS=literal>FileInputStream</tt>,
<tt CLASS=literal>FileOutputStream</tt>, and <tt CLASS=literal>RandomAccessFile</tt>.

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<PRE>
public final class <tt CLASS=literal>FileDescriptor</tt> extends Object {
    // <tt CLASS=literal>Default Constructor: public FileDescriptor()</tt>
    // <tt CLASS=literal>Constants</tt>
            public static final FileDescriptor <tt CLASS=literal>err</tt>;
            public static final FileDescriptor <tt CLASS=literal>in</tt>;
            public static final FileDescriptor <tt CLASS=literal>out</tt>;
    // <tt CLASS=literal>Public Instance Methods</tt>
        <b>1.1</b>  public native void <tt CLASS=literal>sync</tt>() throws SyncFailedException;
            public native boolean <tt CLASS=literal>valid</tt>();
}
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<h3 CLASS=sect2><A CLASS="TITLE" NAME="JNUT2-CH-24-SECT-17.2">Passed To:</A></h3>

<P CLASS=para>
FileInputStream(), 
FileOutputStream(), 
FileReader(), 
FileWriter(), 
SecurityManager.checkRead(), 
SecurityManager.checkWrite()

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<h3 CLASS=sect2><A CLASS="TITLE" NAME="JNUT2-CH-24-SECT-17.3">Returned By:</A></h3>

<P CLASS=para>
DatagramSocketImpl.getFileDescriptor(), 
FileInputStream.getFD(), 
FileOutputStream.getFD(), 
RandomAccessFile.getFD(), 
SocketImpl.getFileDescriptor()

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<h3 CLASS=sect2><A CLASS="TITLE" NAME="JNUT2-CH-24-SECT-17.4">Type Of:</A></h3>

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DatagramSocketImpl.fd, 
FileDescriptor.err, 
FileDescriptor.in, 
FileDescriptor.out, 
SocketImpl.fd

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